There is known a color diffusion transfer photography using an azo dye image forming compound which is adapted to provide, in development under basic conditions, a diffusible azo dye which is different in diffusibility from the parent compound. As examples of image forming compounds capable of releasing a magenta dye, those described in Japanese Patent Application (OPI) Nos. 115528/75, 114424/74 and 4028/80 and U.S. Pat. Nos. 3,932,380 and 3,931,144, for instance, are known. (The term "OPI" as used herein refers to a "published unexamined Japanese patent application".)
However, the compounds described in these prior art literatures invariably comprise .alpha.-naphthols as a coupling component and have the disadvantage of a low dye transfer efficiency or a low light fastness. As the image forming compounds adapted to release a dye comprising a phenol derivative as a coupling component, those described in U.S. Pat. No. 4,473,632 are known. However, the hue of the dye is yellow and there is not known a magenta dye compound comprising a phenol derivative as the coupling component.